Scoop buckets have been around for many years and have traditionally used the similar ejection systems with similar inherent problems. In the mining field, such as coal mining, the low profile scoop cars and scoop buckets use basically the same ejection cylinder and mounting arrangement. The conventional arrangement utilizes a rigid flange mounted cylinder. Using the ejection system to pull loads into the bucket creates tremendous side load forces when the particular load does not slide smoothly into place. These forces are known to cause premature and sometimes instant failure of the ejection cylinder when utilizing the conventional mounting arrangement. When the blade is moved a hammering action is sometimes seen with the conventional setup. This hammering action also contributes to premature ejection cylinder failure.
Known scoop cars and buckets are particularly adapted for handling minerals, such as coal, after it has been loosened and piled in a mine. In the mining field, each scoop bucket is disposed on one end of a traction vehicle to facilitate loading and unloading therefrom using a blade. A track and guide may be provided to maintain the proper positioning of the blade relative to the scoop bucket. Alternatively, wheels have been used to facilitate the movement of the blade relative to the bottom of the scoop bucket.
U.S. Pat. Nos. 3,777,915 and 4,090,627, the contents of which are incorporated herein in their entirety, show similar scoop devices having ejector blades slidably disposed within scoop buckets. U.S. Pat. No. 3,777,915 issued to Reed on 11 Dec. 1973 teaches a mining scoop with an open bucket ejector mechanism operated by a rack and pinion utilizing an accordion type arm structure, having an upper and lower arm pivotally attached to one another, which mechanism operates hydraulically to extend and retract the blade along a rack disposed on the side of the bucket. U.S. Pat. No. 4,090,627 issued to Teti on 23 May 1978 teaches a scoop car having a blade that is extending and retracted using a telescopic hydraulic cylinder disposed between the blade and the closed end of the scoop car, wherein the very end of the telescopic hydraulic cylinder appears to be attached to the blade at the end of a cup-shaped apparatus disposed in the middle of the blade.
U.S. Pat. No. 4,673,131 issued to Travis on 16 Jun. 1987 discloses a mine dusting machine having a scoop bucket and a hydraulic telescoping cylinder arm to extend and retract a blade. U.S. Pat. No. 6,079,933 issued to Moyna et al. on 27 Jun. 2000 shows a hydraulic circuit for an ejector type dump mechanism for articulated trucks and the like. Similarly, U.S. Pat. No. 6,092,973 issued to Burnett et al. on 25 Jul. 2000 teaches a dial-in ejector speed control for articulated trucks and the like having ejector type dump mechanism. An alternative mine car scoop, shown in U.S. Pat. No. 6,176,673 also issued to Moyna et al. on 23 Jan. 2001, shows a tailgate assembly having side mounted hydraulic cylinders.
A variety of mining vehicles also use a telescoping arm for unloading. U.S. Pat. No. 3,349,931 issued to Wagner on 31 Oct. 1967 shows a telescoping unloading truck for use in low ceiling areas. U.S. Pat. No. 3,524,559 issued to Osborne on 1 Apr. 1968 teaches a mining car with a telescopic hydraulic cylinder attached to a plow for emptying the mining car.
Similar devices are also used in agricultural machinery where a truck bed with a scoop is slidably disposed within the bed. French Patent FR1049124A issued 28 Dec. 1953 shows an agricultural truck bed having a retractable blade disposed in the truck bed in which a hydraulic telescoping cylinder is used to extend and retract the blade.
Another use for such devices is in the field of dump trucks, such as garbage trucks. U.S. Pat. No. 3,865,260 issued to Wieschel et al. on 11 Feb. 1975 teaches a refuse body with two-part packer-ejector platen that uses a telescopic hydraulic cylinder U.S. Pat. No. 4,384,816 issued to Martin et al. on 24 May 1983 shows a dump truck which incorporates a telescopic hydraulic cylinder therein. U.S. Pat. No. 4,632,628 issued to Kress et al. on 30 Dec. 1986 teaches a side-ejection vehicle that utilizes a telescopic hydraulic cylinder to dump the contents of the vehicle bed sideways. U.S. Pat. Nos. 6,059,513 issued to 6,059,513 on 9 May 2000 shows a pull-type rear ejector wagon which uses a telescoping arm pivotally connected to a blade at an angle thereto. U.S. Pat. No. 6,062,804 issued to Young et al. on 16 May 2000 shows a load carrying body and ejector arrangement that uses a hydraulic telescoping arm to eject the contents of the carrying body.
Compactors also use such device. U.S. Pat. No. 4,576,540 issued to Derain et al. on 18 Mar. 1986 shows a device for compacting contents of high capacity semitrailer body that incorporates a telescopic hydraulic cylinder to move a compacting blade.